1. Field of the Invention
The present invention relates generally to the field of vehicular seating, and more particularly to an improved device to minimize seat vibration for movable seat backs of the type tethered to a cabin wall.
2. Related Art
Strategies for efficiently seating passengers in a cabin space are desirable in many fields including automobiles, trucks, buses, trains, nautical vehicles and the like. In many instances, a seat will be located with its backrest directly adjacent a wall of the cabin (or a wall in the cabin) and configured as either a “stadium” type seat where the seat cushion and backrest can be folded to an upright, stowed condition, or the seat and back assembly can be shifted forward in a “slouch” configuration. The second row of a pickup truck is a common application for both slouch and stadium seat configurations which are considered attractive to purchasers.
Although prior art movable seat back designs work reasonably well, they tend to be the source of much buzzing, squeaking and rattling (BSR) noises. In both stadium and slouch-seating arrangements, a rigid, metallic striker wire or pin extends from the cabin wall. A rigid metallic latch bracket on the movable seat back, having an elongated, generally U-shaped slot formed therein, hooks over the striker pin to tether the seat back to the cabin wall. The elongated U-shaped slot allows the seat back to move between its various positions while remaining tethered to the cabin wall. However, this point of connection between the seat back and the cabin wall generates the vibrations that result in objectionable BSR noise.
Various proposals have been advanced to address the BSR concern arising from vibrations between the striker pin and the latch bracket. One example is illustrated in U.S. Pat. No. 7,270,371 granted Sep. 18, 2007. In this reference, it is suggested to line the U-shaped slot in the latch bracket with a plastic insert to dampen noises. This technique, in fact, is fairly well known in the seating environment, as depicted in non-stadium and non-slouch seating configurations such as U.S. Pat. No. 6,283,550 granted Sep. 4, 2001, and U.S. Pat. No. 4,759,580 granted Jul. 26, 1988. In these examples, a static, anti-noise or vibration dampening part is associated with a hook slot of the seat frame to prevent metal-to-metal contact with an anchoring pin.
Prior art attempts to eliminate or minimize BSR in a vehicle seat are only partially effective. Because the vibration dampening inserts are static, i.e., they are rigidly and immobly fixed relative to the latch bracket, vibrations albeit dampened are still transmitted directly into the seat frame and/or other surrounding rigid structures and resonate with BSR symptoms.
Another issue with stadium and slouch seat configurations is the inevitable dimensional variances between the diameter of the striker pin and the width of the slot in the latch bracket. In one extreme, excess play in this sliding connection will intensify BSR and premature wear. In the other extreme, a tight fit may result in stiff operation and premature wear. Accordingly, there is a need to further eliminate or further minimize seat vibrations when a movable seat back is tethered to a cabin wall, and to better accommodate dimensional variances between the manufactured components of the sliding latch bracket connection.